Quite the unique concept for an ancestry you've made! The idea of community really shines in all of its features, and the included rival is a sweet love letter to Draw Steel's releases this past year.
As far as critiques go, Last Grasp feels more draining than collaborative. A rewrite to emphasize your allies putting themselves on the line with a title like We Stand Together! or something similar would emphasize the narrative I think you're looking for. Additionally, One With the Team is quite cool and I like the angle of it, but any ability that lets a player swap features around on a rest is going to be much stronger than just having one static feature. I'd consider shifting it to picking the ability when the party is established (encourage more player collaboration with the communal spirit, perhaps?)
This is a very strange (positive) yet very fun submission. I'll certainly take some notes from it.